PDA

View Full Version : Brushless AXI 2814-12 cutting out


rcAirTycoon
09-24-2005, 01:10 AM
This is the setup I've got on a SIG Little Extra glo to electic conversion.

AXI 2814- 12
30 amp JETI Advance
4200maH TP LiPoly

After about 3 min of flight time at half throttle the motor cuts off - it cuts off after 30 seconds at full throttle.

I'm getting 32 Amps draw at half to full throttle.

This is the setup Hobby Lobby recommended and I've tried to get help but nothing works. I've tried relocating the speed control to maximize air flow, change prop to 8x6 (the smallest recommended prop is a 9x5.5), The battery never drops below 12 volts.

any ideas? The next up speed control is a 40 amp but the motor is only rated to 35 amps.

Is it possible that the battery is over-amping the ESC? The LHS didn't think that was possible.

Appreciate any help since the set up cost $300 and I'd like to get it to work!

thanks! J

ptglass
09-24-2005, 05:12 AM
I assume you bought this at HL. Did you give them a call and let them try and sort it out?

I would wonder if the speed control was defective. Everything should be working as advertised.

soarr
09-24-2005, 06:54 AM
It's quite possible that you have a defective ESC. Can you get the problem to happen consistently?

watt_the?!
09-24-2005, 09:41 AM
am i missing something here ?....you are drawing 32A on a 30A ESC.

even if this has happened once, it could be fried, so changing back to lower power setups may not help as it may now not be functioning.

on the other hand it is marginal, but if you have a 32A setup you should be looking at at least 40A ESC.

Tim.

...
...

Is it possible that the battery is over-amping the ESC? The LHS didn't think that was possible.



ummm, the LHS would be wrong. it is very possible...thats how they fry.

the prop/motor will take what it needs. The ESC will supply the load as required...even if it is 60A. But if it is rated at 30A, 60A is way over stress, which is the primary killer of electronics.


edit: is is weird that the battery doesnt drop below 12V though...in fact extremely unusual....are you sure?....

ragbag
09-25-2005, 06:10 AM
32 amps at half throttle with a 30 amp control doesn't sound right, what in the world are you asking the 30 amp control to do full wide open? You are already bumping the wall at 32 with a 30 amp controller. Cant remember which one at Hobby Lobby made the remark, but he said to always go over the amps on the controler and not over stress it.
My thoughts,
By George

rcers
09-25-2005, 07:31 PM
but he said to always go over the amps on the controler and not over stress it.

Huh? What? Always go over the controller's AMP rating? Don't know who said that but they don't know what they are talking about.

Mose controllers have over-amp ratings for a few seconds (usually 5-30 seconds) but you should not exceed that time frame.

I always under amp mine, for safe measure. No reason not too.

Mike

Twmaster
09-25-2005, 09:47 PM
Huh? What? Always go over the controller's AMP rating? Don't know who said that but they don't know what they are talking about.

Mose controllers have over-amp ratings for a few seconds (usually 5-30 seconds) but you should not exceed that time frame.

I always under amp mine, for safe measure. No reason not too.

Mike

Hehe at first I miss read George's post. What he said (in other words) was always buy a bigger ESC than you need. For example, buy a 30A control if you think you would be pulling 25A constantly. At least I -hope- that's what George meant! ;)

rcAirTycoon
09-26-2005, 12:32 AM
Thanks for all the feedback!

I finally got through to somebody at HL and they have requested that I send the ESC and motor back to them so they can troubleshoot and replace it for me. The gentleman I spoke to told me that the average amp draw through to that motor should typically be around 24--so something's misbehaving.

It's boxed up and ready to go... I'll post again when I learn more from Hobby Lobby

J

Duster52
10-07-2005, 11:32 AM
I'm getting 32 Amps draw at half to full throttle.



I don't know what you mean. There is a lot of difference in amp draw at half throttle and full throttle. It can't be a flat 32 amps, unless something else is wrong. 32 amps at half throttle could mean 60 amps at full throttle. Which is it?